It is common to provide tamper indicating closures to indicate when a closure has been removed from a container. Typically, one type of such closures includes a tamper indicating band that is attached to the skirt of the closure along a weakened line and has means for engaging a retaining bead on a container. When the closure is removed, the retaining bead restricts movement of the tamper indicating band causing the band to be severed. Typical tamper indicating closures of this type are shown in U.S. Pat. Nos. 33,265 and 4,653,657.
It has also been suggested that tamper indicating bands be provided with means for retaining the bands on the closures.
Among the objectives of the present invention are to provide a tamper indicating closure having a novel construction for retaining the tamper band on the closure while still providing visual evidence of the closure having been removed from the container; which the closure is readily manufactured without additional manipulative steps such as selective scoring; and which can be provided by the molding operation of forming the closure.
In accordance with the invention, a tamper indicating closure comprising a base wall, a peripheral skirt and a band connected with the skirt along a weakened line. The band includes portions that are adapted to engage an annular retaining bead on a container to which the closure is applied. The closure includes a thin membrane extending axially along the lower portion of the skirt, spanning the weakened line and through the band. A thickened band retention column extends radially inwardly the inner surface of the lower portion of the skirt adjacent the thin membrane, and axially spans the weakened line and extends radially outwardly into the band When the closure is removed from its position on the container, the score line and thin membrane are broken but the band retention column retains the band on the closure and indicates that the closure has been tampered with.